The present invention relates to a valve assembly for a hydraulic discharge device and including a piston displaceable in a bore of a housing of the discharge device against a biasing force and having an outer surface, which sealingly engages an inner wall of the housing bore and blocks a channel opening into the bore so that the piston functions as a slide valve for this channel.
The valve assembly of this type are used, e.g., for controlling fluid flow from the discharge device to an actuator. The drawback of the valve assembly of this type consists in that a leakage of pressure fluid between the engageable surfaces of the piston and the bore wall exists. Therefore, the discharge device should always provide an additional amount of fluid flow to compensate for this leakage.
Accordingly, an object of the invention is a valve assembly of the above-mentioned type with improved sealing characteristics, which insure a good control stability of the slide valve.